19
substitute(noun, adjective, agent, representative, alternative)
16
alternate(noun, adjective, lower, copy, inferior)
14
stand-in(noun, adjective, cover, reserve, substitute)
12
reserve(noun, adjective, support, increase, lower)
12
support(noun, adjective, help, increase, praise)
11
backing(noun, support, help, praise, benefit)
10
relief(noun, adjective, support, help, praise)
9
surrogate(noun, person, thing, agent, substitute)
9
understudy(noun, adjective, reserve, substitute, replacement)
8
alternative(noun, adjective, spare, extra, substitute)
8
auxiliary(noun, adjective, support, increase, lower)
8
deputy(noun, adjective, help, aid, reserve)
8
replacement(noun, adjective, reserve, extra, agent)
8
spare(noun, adjective, support, reserve, extra)
7
fill-in(noun, adjective, copy, reserve, substitute)
7
patronage(noun, support, help, benefit, aid)
7
secondary(noun, adjective, support, increase, spare)
7
supportive(adjective, informal, spare, reserve, secondary)
6
backup man(noun, expression, idiom)
6
double(noun, adjective, reserve, substitute, replacement)
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APASmart Define. (2015). backup thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/backup/thesaurus/synonyms
ChicagoSmart Define. 2015. "backup thesaurus" https://smartdefine.org/backup/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, backup thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/backup/thesaurus/synonyms>.
MLASmart Define. "backup thesaurus" 10 April 2015. Web. 20 September 2026. <https://smartdefine.org/backup/thesaurus/synonyms>